Android's Interesting Problem

Some months back, the wifi in my Sony Xperia Z3 Compact stopped working. I had assumed it was a software problem at the time, because these sorts of things usually are. This led me down a miserable, annoying little rabbit hole of forum posts, spec sheets, and eventually a talk with Sony customer service.

Photo credit: http://blog.clove.co.uk/wp-content/uploads/2014/09/Sony-Xperia-Z3-Compact-back.png

It all began one fateful afternoon, when I was dorking around on my phone instead of doing my homework. I was probably looking at dank memes on imgur or something equally pointless. Regardless, the wifi disconnected from my home network, and the wifi shut off. I thought nothing of it, as our home wifi serves upwards of 25 devices and does that from time to time. So I go around and shut off all of the stuff I'm not using (iPad, Vita, Desktops) and try to reconnect. It would reconnect, but then disconnect shortly after. I restart it, and the connection holds until the next morning. "Ah well", I thought, "I can't connect to the school's wifi anyway, so I'll fix it when I get home". I come home after school and do a factory reset. This holds for about an hour, then fails. Try it again, it doesn't work at all. I try using the Xperia PC Companion, and the same thing happens. Five minutes or so, then fails, never to work again. I try using the "Testing Menu" code from the calling app, and the same thing happens. I try FXR Wifi Fix and Rescue, and that will get about halfway through and the app will hang. I run the diagnostics thing in "Settings > About > Diagnostics" or something like that, and it says bluetooth is bad but Wifi is a-OK. Which it clearly isn't, I might add. I then twiddled my thumbs for a bit, and gave up. This was about a month ago, and the problem still hasn't been fixed, through my efforts or any other supreme being.

I decided to broaden my search. Previously, all of my google entries had been something along the lines of "Fix sony xperia z3c wifi" or "xperia z3c wifi problem" or "sacrifice goats to fix wifi" (no goats were harmed). All this turned up were a bunch of discontented people bitching on the Sony Forums, and a bunch of Sony bots/moderators that were spewing the same three cut and paste answers. Anyhoo, I thought I'd see if the problem was related only to Sony devices. I found a thread on the Google forums about the Nexus and some others that proved to me the problem was not local only to Sony (don't have the link, I'm afraid). Now theoretically, this should mean that the problem is in software, right? I mean, it's a problem across several different manufacturers, with different wifi chips and the like. Well, the multiple reinstallations of the OS and reports by several people that installing/removing custom roms not fixing it seem to say otherwise, that it is a hardware problem. What could cause a fairly widespread hardware problem across multiple manufacturers and devices? Is it even a hardware problem?

I have a theory. I think it is a hardware problem. Most of the forum posts said that the wifi stopped working shortly after a large software update. Updates where the wifi chip is used a lot, and gets fairly warm. Updates where, if not properly ventilated, the phone could get hot enough to reflow solder. I know for a fact that my phone got really, really hot during my meme browsing homework sessions, and it certainly wasn't helped by the fact that the back glass had cracked and was covered in electrical tape in my attempt to fix it. Nor was the fact that it had a case on it helping the matter. My theory is that, during heavy loads, the solder holding the wifi chip to the board melts *just enough* that it can disconnect one or two pins on the BGA and thus break the wifi and possibly bluetooth connectivity, if the right pins are broken. This theory is helped by several reports of people applying "percussive maintenance" to their device, or even going as far as to reflow the wifi chip and getting it to work again.

The fact that this happens on what appears to be a wide range of devices is still a bit befuddling. I'll also admit that it is pure speculation beyond this point (and really a lot before now, too). I think that the phones are not designed to disperse as much heat as they give off with a case on. That last part is important, and you can tell because it's italicized. The cases people use hold in a lot of heat, and make wonderful insulators. I can confidently say this because I used my phone several times without a case and it nearly burned my hand, but never even came close to doing that with a case on under similar loads. I'm not suggesting you go and throw out whatever cases you have, I would however suggest that you take off the case and put it in a cool area when doing a lot of downloading to prevent accidental reflowing of the wifi chip.

Again, this is all pure speculation, and if you have any other theories about why this happens so frequently please do not hesitate to leave a comment. The best way to figure this thing out is to do it together.